In data center environments, rack units may house many server devices, e.g., blade servers. Each server device may be configured to host one or more physical or virtual host devices. The servers in the rack units are connected to, e.g., Top of Rack (ToR) switch devices. The switches, in turn, are connected to other switches via a spine switch or spine fabric. Data in a communication session may be exchanged between host devices (physical and/or virtual) in the same or different rack units. For example, packets of data in the session may be sent from a host device in one rack unit to a host device in another rack unit using network or fabric links.
The packets may be routed between by a first switch coupled to a corresponding spine crossbar and a second switch in the rack unit or another rack unit, or otherwise forwarded out of the first switch, e.g., to a client device or a Storage Area Network (SAN). Data received into the switch may use a parallel data bus. By virtue of this parallel structure, when a packet, e.g., of variable size, does not fill a multiple byte size of the parallel bus used for transmission, then any unfilled data slots are filled with empty idle bytes, thereby potentially wasting data transmission bandwidth.